ROSS, J.
This is an action for damages under the Employers’ Liability Law (Civ. Code 1913, pars. 3152-3162). The facts as to how the accident happened causing the plaintiff’s injury are not controverted. The plaintiff was working for defendant in its mine on the 900-foot level, and on February 3, 1918, while standing on what is designated in the pleadings and evidence as a grizzly^ breaking rocks with a hammer, as he had been instructed to do, the head of the hammer flew off of the handle and struck his right foot, breaking a toe. The grizzly consisted of railroad rails, placed parallel to each other and about six inches apart. When the head of the hammer struck plaintiff’s foot, the foot slipped between the rails, plaintiff lost his balance and fell, wrenching and twisting the muscles, ligaments, and bones of his foot and ankle.
The defendant raised the question of the sufficiency of these facts to constitute a cause of action under the Employers’ Liability Law, by demurrer, and at the trial by a motion for a directed verdict. The demurrer was overruled, and the motion for a directed verdict was refused. The plaintiff had judgment for $2,500, and the appeal is from the judgment and the order overruling the motion for a new trial.
[546]*546The orders overruling demurrer and refusing to grant motion for a directed verdict are assigned as error. We state the defendant’s proposition of law in its own language:
“They [the facts] show that the accident was proximately caused by the head of the hammer flying off and striking plaintiff’s right foot. This is not an inherent risk of a hazardous occupation which is unavoidable by a workman. It is not an accident arising out of and in the course of his employment, and due to a condition or conditions of such employment, as is contemplated by our Employers’ Liability Law, but is the ordinary risk, the ordinary happening which might take place on the public highway, if he were breaking stones there.”
In other words, the proposition amounts to this, as we understand it: The proximate cause of the accident being the negligence of defendant in furnishing plaintiff with a defective hammer to do his work, the injury arose from an ordinary risk, and not an inherent or hazardous risk, it being the contention that the Employers’ Liability Law covers only the latter kind of risk; that is, risks that are inherent in the occupation.
To sustain its position, the defendant refers us to many cases decided by this court, in which the elements going to constitute the cause of action under the liability law have been discussed, and points out therein many expressions tending to uphold its contention. The particular expression upon which the defendant relies is that we'have said in those cases that “the risks and hazards must be inherent in the occupation” before the employee may recover.
That the defendant’s position may be well understood, we again quote from its brief:
“Before an injured workman can recover under the Employers’ Liability Act, it must affirmatively appear that the accident causing the injury was due [547]*547to an inherent risk or hazard of the occupation, and was unavoidable by the workman. This excludes accidents due to the employer’s negligence.”
The learned counsel for defendant rely almost wholly upon what this court has said in other cases to vindicate and sustain their proposition. For instance, in Arizona Eastern R. R. Co. v. Mathews, infra, this language is used:
“It is evident that the accident must arise out of and also be inherent in the occupation itself; the condition or conditions that produce the accident must inhere in the occupation. ... It would seem that, before an employee may recover for injury under this act, it must have occurred while he was at work in his occupation, and it must have been occasioned by a risk or danger inherent in the occupation.”
In Calumet & Arizona Min. Co. v. Chambers, infra, it is said:
“The surroundings in which plaintiff was performing his duties are described in the complaint with sufficient fullness to show that the risks and hazards assumed by the employee are great and inherent in the occupation, and unavoidable by the workmen. . . . Consequently, the facts pleaded are sufficient to set forth conditions of plaintiff’s employment which require him to assume risks and hazards inherent in the occupation he was then engaged in, which he was not able to avoid, and continue in the occupation.”
In Arizona Copper Co. v. Burciaga, infra, it is said:
“The wrong giving the right of action is attributable, not to any fault, wrong, or negligence of the employer, but to the risks and hazards which are inherent in such occupation, and which are unavoidable by the workmen therein. ... As clearly intimated by this court in Inspiration Consolidated Copper Co. v. Mendez, 19 Ariz. 151, 166 Pac. 278, 1183, the Employers’ Liability Law is designed to give a light of action to the employee injured by accident occurring [548]*548from risks and hazards inherent in the occupation and without regard to the negligence on the part of the employer.”
In Inspiration Consolidated Copper Co. v. Mendez, infra, it is said:
“The appellant contends, and I think his contention is correct, that the liability statute must be construed as one creating a liability for accidents resulting in injuries to the workmen engaged in hazardous occupations due to the risks and hazards inherent in such occupations without regard to the negligence of the employer, as such negligence is understood in tlie common law of liability; in other words, such statute creates a liability for accidents arising from the risks and hazards inherent in the occupation without regard to the negligence or fault of the employer.”
In Superior & Pittsburg Copper Co. v. Tomich, 19 Ariz. 182, 165 Pac. 1101, 1185, it is said:
“The matters left open for inquiry were the amount of the damages the plaintiff was entitled to recover as measured by the allegations of the complaint and the evidence, and whether the accident was due to a condition or conditions of the employment, and such as is unavoidable.”
Counsel also contend that the Supreme Court of the United States, in Arizona Copper Co. v. Hammer, 250 U. S. 400, 63 L. Ed. 1058, 39 Sup. Ct. Rep. 553, in construing the Arizona Liability Law, and the decisions of this. court, also had in mind that the liability created was one arising out of accidents inherent in the occupation, and quotes many expressions from that high court such as: “Employment designated as inherently hazardous and dangerous to workmen”; “to hazards inherent in the employment”; “risks inherent in the occupation”; and “due to such inherent conditions.”
[549]*549As we. go along, we think we shall be able to show that the liability arises when the injury or death is caused by an accident due to a condition or conditions of the occupation, and that the accident need not necessarily happen by reason of an inherent risk or danger, but that it may arise from the manner in which the business is carried on. Section 7, article 18, of the Constitution is the fountainhead and source of the Employers Liability Law. It creates and defines a new liability of the employer to the employee. It names and points out the circumstances and' conditions under which the liability may arise. It defines the rights that may accrue to an injured or killed employee, and directs the legislature to enact a law providing a method of procedure for the enforcement of those rights. The mandate to the legislature contained in said section adds nothing to the rights therein created. If the Constitution had stopped with the bare declaration of the right, the duty of the legislature to enact laws for its enforcement would have been just as imperative. The provision was not self-executing, and, whether commanded to supplement it with proper legislation or not, the obligation to do so was obvious, if the intention as expressed in the Constitution was to be carried out. So the direction to the legislature was not to create a new or different right of action, or to add to or take from the one declared by the Constitution, but to formulate laws whereby the rights secured may be realized. According to the definition, the liability of the employer depends upon the concurrence of the three following circumstances: (1) The existence of the relation of employer and employee; (2) injury or death while in the service of the employer in a hazardous occupation in one of the industries of mining, smelting, manufacturing, railroad, or street railway transportation, or other [550]*550proper industries; (3) the injury or death must have been caused by an accident due to a condition or conditions of the occupation, and not caused by the negligence of the employee killed or injured. If the relation of employer and'employee exists, if the latter suffers injury or death in a named hazardous occupation caused by an accident due to a condition or conditions of the occupation, and not the negligence of the employee, all the constitutional facts are present, and constitute a right of action in favor of the employee against the employer. The legislature, in paragraph 3154, Civil Code (part of the Employers’ Liability Law), has phrased the definition of the right thereby created in the language of the Constitution, and has said that the concurrence of the circumstances named above will give rise to a right of action in favor of the employee.
It is declared and determined in paragraphs 3155 and 3156 that the occupations in ten classifications of industries therein enumerated are hazardous within the meaning of paragraph 3154, and section 7, article 18, of the Constitution; and in paragraph 3158 it is provided that the injured employee may maintain the suit, and, in case death ensues, that the right of action survives in favor of the persons therein named in the order given.
However, the legislature, in paragraph 3155 has undertaken, by an independent observation of its own, to explain, not so much the right of action as defined, as the dangerous character of the occupations declared to be hazardous, and for that purpose has employed this language:
“By reason of the nature and conditions of, and the means used and provided for doing the work in, said occupations, such service is especially dangerous and hazardous to the workmen therein, because of risks and hazards which are inherent in such occupa[551]*551lions and which are unavoidable by the workmen therein. ’ ’
This we take it, was more in explanation of the reason for imposing this new liability upon the employer than an effort to add to or take from the right of action new elements, or elements other than those named in paragraph 3154 and section 7 of article 18 of the Constitution. The legislative statement that in the occupations named the means used and provided for doing the work are dangerous and hazardous, and the risks and hazards therein inherent and unavoidable, may be taken for granted, but at that' it is not a declaration that the accident causing the injury or death must have occurred from an inherent danger, or have been unavoidable, before a recovery could be had. The definition of the right is that the injury or death must have been “caused by an accident due to a condition or conditions of the occupation.” The legislature had no power to add to or take from this definition. Cooley on Constitutional Limitations, page 99, says:
“Another rule of construction is, when the Constitution defines the circumstances under which a right may be exercised, . . . the specification is an implied prohibition against legislative interference to add to the condition. ...” State v. Osborn, 14 Ariz. 185, 125 Pac 884; 12 C. J. 750.
A limitation on the legislative power may be by direct prohibition or by implication, and when it is by implication its restraints on the legislature are no less binding than when expressly prohibited. The command to the legislature to enact a law making the employer liable to the employee when the latter is injured or killed “by an accident due to a condition or conditions of the occupation,” and not due to the employee’s negligence, impliedly prohibits the legislature from changing the circumstances giving [552]*552rise to the right of action, for, if the legislature may change it in one respect, it could, while pretending to uphold it, so encumber the right as to abolish it altogether, or, on the other hand, could disregard it and extend a right and remedy to the employee under any and all circumstances. But, as indicated above, we do not think the legislature, in its general observation as to the lethal character of the occupations named, intended to qualify or change the elements the Constitution says shall constitute the right.
We are of the opinion that the rights of the employer and employee under this law, when submitted to a court for adjudication, must be determined and settled in accordance with the constitutional definition, that is, the injury or death must have been “caused by an accident due to a condition or conditions of the occupation,” and “shall not have been caused by the negligence of the employee killed or injured.”
Labor and service in the occupations enumerated are declared and determined to be hazardous. The Standard Dictionary defines hazardous as “exposed to, exposing to, or involving danger, risk of loss or calamity; perilous, risky.” The character of the labor or service, therefore, is such that the employee while engaged at his work continuously exposed to danger or risk of loss, and this is true regardless of any precautions on his part or on the part of the employer.
The hazards to which the employee is exposed may be greatly minimized by introducing into the work, and for the employee’s protection, the latest and most approved safety appliances and devices, or the hazards may be multiplied by “slipshod” methods or indifferent attention by the employer to the safety of the employee. This contingency was doubtless in the minds of the lawmakers when they made the [553]*553liability of tbe employer depend npon an injury or death “caused by an accident due to a condition or conditions of the occupation,” rather than the lack of care or precaution to prevent accidents. This unusual liability, it would seem, was primarily placed upon the employer, to stimulate him to put his business in the safest possible condition, and thereby reduce the number of accidents, and accordingly his liability; for in both the Constitution (section 7, art. 18) and in the statute (paragraph 3154) the introductory words are “to protect the safety of employees in all hazardous occupations” — the principle of liability herein is declared. While the law does not undertake to regulate the conditions of the occupations declared to be hazardous by requiring the use of safety appliances and devices, it does provide in paragraph 3157, Civil Code, that the employer “shall by rules, regulations or instructions, inform all employees in such occupations as to the duties and restrictions of their employment, to the end'of protecting the safety of employees in such employment.” These expressions are admonitions to the employer that the extent of his immunity from liability to the employee for injury or death depends upon a strict observance of the slogan “safety first,” by the application to his business of every possible means to prevent accidents. It is the declaration of a policy that may and will affect all employers, but its burdens will fall most lightly upon the ones who diligently endeavor to protect their employees from accident, and this knowledge will stimulate all to do all things possible and necessary, from selfish, if no higher, motives, to save expenses and protect their business.
The dictionary definition of the word “condition” is:
“Mode or state of being; state or situation with regard to external circumstances; essential quality; property; attribute.” Webster.
[554]*554The state of the work or service in the occupation or the essential qualities, properties or attributes of the employment have reference to all of the situations and circumstances surrounding such employment, that is, the condition or conditions may be good or poor, may be favorable or unfavorable, may be safe or unsafe, or the last word in perfection. But, under the statute, the liability of the employer does not depend upon the existence of one or the other. "Whatever the condition or conditions, whether good or bad, the liability depends upon the accident being due to them. It follows, therefore, that the negligence of the employer in failing’ to furnish the employee a safe place to work, or safe tools and implements with which to work, is not the ground upon which his liability is based, inasmuch as he is liable even though he may furnish the employee a safe place to work and safe tools and implements with which to work, if, notwithstanding, the employee is injured or killed by an accident due to a condition or conditions of the occupation. In the former case accidents will be more frequent; more employees will be killed or injured, and the business will have to bear a greater burden because of the negligence, but that does not change the principio upon which the right of action is based.
The condition or conditions that cause the accident resulting in injury or death may be inherent in the occupation, or they may arise from the manner in which the business is carried on. The conditions of the occupation in which the employee does his work involves, not only the place he works, but the tools with which he works, the one as much as the other. He cannot perform his work without tools, nor without being in the place assigned to him. In the present case he could not break rocks without the hammer, nor determine the sizes into which they should be broken [555]*555without the grizzly, nor do his work without being on the grizzly. These circumstances, and others that might be named, went to make up the conditions of his work in the hazardous occupation of mining in which he was engaged when injured. The fact that there was a defect in one of the conditions of his work, to wit, in the hammer, does not relieve the employer from liability any more than he would have been relieved from liability for an injury by a piece of flying rock caused by a blow of the hammer. In other words, if in handling a perfect hammer with ordinary care, the employee had been injured by an accident due to a condition or conditions of his work, the employer could not claim exemption from liability. The employer cannot negligently create nor permit a condition, and when an accident results therefrom plead it as a bar to the action, any more than he can claim exemption because the conditions were perfect. We conclude that the contention of defendant that the injury must have been caused by a risk or hazard inherent in the occupation before a recovery could be had is without merit. And it is equally clear the defendant cannot avail itself of its own negligence to defeat the action.
The only thing that will defeat the action and absolve the employer from liability is the negligence of the employee. If the injury or death be not caused by an accident due to á condition or conditions of the occupation, but is caused by the negligence of the employee, he cannot recover, nor can his personal representative or beneficiary. The only risk or hazard the employee assumes is his own negligence.
The conclusion at which we have arrived in this case is not in keeping or accord with what this court has said in Calumet & Arizona Min. Co. v. Chambers, 20 Ariz. 54, 176 Pac. 839, Arizona Copper Co. v. Burciaga, 20. Ariz. 85, 177 Pac. 29, Arizona Eastern R. Co. [556]*556v. Matthews, 20 Ariz. 282, 7 A. L. R. 1149, 180 Pac. 159, Inspiration Cons. Copper Co. v. Mendez, 19 Ariz. 151, 166 Pac. 278, 1183, Superior & Pittsburg Copper Co. v. Tomich, 19 Ariz. 182, 165 Pac. 1101, 1185, and perhaps other cases, in an effort to define the right of action under the Employers’ Liability Law; but, after much reflection we do not think the expression of opinion in those cases is a correct exposition of the law. The writer hereof has long felt (Superior & Pittsburg Copper Co. v. Tomich, supra, dissenting opinion) that the construction of the law as contained in the above cases unjustifiably and unduly limited and qualified the right of action given the employee by the statute and Constitution,-and feels no embarrassment in overruling those cases to the extent herein indicated.
The defendant also assigned as error the giving of the following instructions."
“(1) If the jury find the issues for plaintiff, then the plaintiff is entitled to recover such actual damages as the evidence may show he has sustained as the direct or proximate result of such injury, taking into consideration his loss of time, his pain and suffering, his necessary and reasonable expenses in medical and surgical aid, so far as the same appear from the evidence in this case. ...
“(2) . . . What moneys, if any, he may have been compelled to lay out in medical treatment, medicines or nursing, and what moneys he will be obliged to pay out in the future for medical or surgical treatment or medicine, if any. ... ”
The defendant contends that these instructions are erroneous, in the respect that they authorize the jury to include in its verdict, past expenses for medical and surgical aid, medicines, and nursing, and also future expenses that he may be put to on the same account.
[557]*557The only evidence hearing upon this question is to the effect that the plaintiff was taken to the defendant’s hospital, where he- received medical and surgical aid and nursing for the period of two months, and that after he was discharged from the hospital, four X-ray pictures of his foot and ankle were taken by a surgeon who testified in the case. There is no evidence that the plaintiff paid for any of this service, or that he assumed any obligation on account thereof. Nor is there any evidence of the value of the surgical and medical services rendered the plaintiff. While we think it might be assumed that no charges for his treatment at the defendant’s hospital were contemplated, and that the jury knew this, this much may not be said with respect to the examination by the surgeon who took the X-ray photographs of his foot and ankle. The evidence as to future expenses for medical and surgical treatment, or the probability of any, is equally impotent. That these elements of damage may properly be included in the verdict, when established by legal evidence, we think is well settled. They should, however, not be submitted to the consideration of the jury as elements entering into the damages that the plaintiff sustained, unless he has either paid them or incurred a liability on that account, and not even then without proof of their value.
“When . . . such damages are susceptible of proof with approximate accuracy, and may be measured with some degree of certainty, they should not be left to the guess of the jury, even in actions ex delicto. Parsons v. Railway Co., 94 Mo. 286, 6 S. W. 464; Pritchard v. Hewitt, 91 Mo. 547, 4 S. W. 437; 2 Thompson, Trials, § 2077. When so left, it is impossible to tell to what extent a verdict may have been affected by the vague estimates the jury may have placed upon the values, concerning which there was no proof; consequently it is impossible to say [558]*558the jury was not prejudiced by this erroneous instruction upon the question of damages. ... In Reed v. Railroad Co., 57 Iowa, 23, 10 N. W. 285, the question presented was directly raised. The Supreme Court of Iowa say: ‘Under the instruction in question the jury were directed to include compensation for medical services in their verdict. They doubtless would feel authorized to determine the amount to be allowed therefor, according to their own judgment, without aid of evidence; but the law cannot be administered in this uncertain way. Damages of this kind cannot be found by the jury except upon proof. It will not do to say that the amount of damages allowed by the jury may have been small. We can know nothing about the amount, and, if we could know it to be insignificant, we could not relieve this case from the operation of the familiar rules of law which require damages of the character of those under consideration to be established by proof.’ ” Chicago etc. R. Co. v. Butter, 10 Ind. App. 244, 38 N. E. 1, loc. cit. 5; Cincinnati H. & D. R. Co. v. Armuth, 180 Ind. 673, 103 N. E. 738; Indianapolis etc. Co. v. Hensley (Ind.), 105 N. E. 474; Moran v. Dover etc. Ry. Co., 74 N. H. 500, 120 Am. St. Rep. 994, 19 L. R. A. (N. S.) 920, and case note, 69 Atl. 884.
The above cases refer to past medical services, and the evidence necessary before they may be submitted to the jury as elements of damage. The evidence with reference to medical services expected to be necessary, furnishes no data whatever upon which to base any compensation to the plaintiff.
As was said in Page v. President etc. Co., 34 App. Div. 618, 54 N. Y. Supp. 442:
“True, for such services it could not be fixed with the accuracy that it could for those already rendered; but some proof, at least, might have been given by the expert witnesses who testified as to the permanent character of the injury, not only whether medical services would thereafter be needed, but also as to their character, and their probable duration and value. . . .
[559]*559“Any attempt to fix the amount of the expenses so liable to be incurred would be the purest guesswork. For that reason the case was not one in which a jury could lawfully estimate and allow compensation for such ‘prospective future expense,’ and the instruction that they might do so was error.”
It is not possible for anyone to say what amount the jury may have allowed the plaintiff for past and future medical and surgical aid. They were told, however, that they might consider these as elements in making up the plaintiff’s damages, and, since there was no evidence that the plaintiff had expended or contracted to expend anything, or that there was a probability that he would in the future have to do so on that account, whatever was included in the verdict for medical treatment must of necessity have been arrived at by mere guess.
The plaintiff stated his cause of action in two counts: One under the liability law and one under the common law. Defendant complains that the court erred in not requiring plaintiff to elect upon which cause of action he would proceed before the trial was begun, and in permitting the plaintiff to read both causes of action to the jury. It does not appear that the defendant was or might have been prejudiced by this action of the court.
The defendant’s answer raised other questions, but they were all, except the ones we have considered, abandoned on appeal. The only propositions presented to this court for determination are the ones that we have gone into.
For the error committed in giving these instructions, we find it necessary to reverse the case, with directions that the defendant be granted a new trial.