 The hypotheses that arise from experiment are verifiable hypotheses. The process of generalization presupposes a belief in the unity and simplicity of nature (see 1902: 161 ff.; 2017: 105 ff.), although it is important to remember that for Poincaré experience is always a complex phenomenon that is theory laden. Any good experiment in physics can be generalized in an infinite number of ways, depending on our preconceived ideas, and every generalization results in a hypothesis. While he emphasizes the creative role of the scientist, Poincaré does not go so far as to say that natural laws are simple definitions, as Le Roy proposed (1901: 143).