over and running for so many times acts which a medical book considered as contributory factors that would increase intraocular pressure which causes glaucoma. Aside from the physical demands of the job, petitioner contends that he was also subjected to emotional strains of going through the perils of the sea and homesickness for being away from his family during the entire duration of the contracts. He, thus, alleges that his employment as a seaman contributed, even in a small degree, to the development of his ailment.   In fine, petitioner stresses that, as a social legislation, P.D. No. 626, as amended, should be interpreted to give meaning and substance to the liberal and compassionate spirit of the 1987 Constitution and the Labor Code.   The petition lacks merit.   Under the Labor Code, as amended, an employee is entitled to compensation benefits if the sickness is a result of an occupational disease listed under Annex "A" of the Rules on Employees' Compensation; or in case of any other illness, if it is caused by employment, subject to proof that the risk of contracting the same is increased by the working conditions.[14] This is as it should be because for an illness to be compensable, it must be (1) directly caused by such employment; (2) aggravated by the employment; or (3) the result of the nature of such employment. [15]  Jurisprudence provides that to establish compensability of a non-occupational disease, reasonable proof of work-connection and not direct causal relation is required.[16] It is enough that the hypothesis on which the workmen's claim is based is probable.[17] Probability, not the ultimate degree of certainty, is the test of proof in compensation proceedings[18] since in carrying out and interpreting the provisions of the Labor Code and its implementing rules and regulations the primordial and paramount consideration is the employees' welfare.   In the present case, petitioners chronic open angle glaucoma is not listed as an occupational disease; hence, he has the burden of proving by substantial evidence, or such relevant evidence which a reasonable mind might accept as