# Ayala, ‘Autonomy of Biology as a Natural Science’, 1972 > [!cite] > Ayala, Francisco J. ‘The Autonomy of Biology as a Natural Science’. In *Biology, History, and Natural Philosophy: Based on the Second International Colloquium Held at the University of Denver*, edited by Allen D. Breck and Wolfgang Yourgrau. Plenum Press, 1972. [http://archive.org/details/isbn_9780306305733](http://archive.org/details/isbn_9780306305733). --- ‘The goal of science is the systematic organization of knowledge about the material universe on the basis of explanatory principles that are genuinely testable.’ [[Ayala, ‘Autonomy of Biology as a Natural Science’, 1972|(Ayala 1972, 1)]] ^a8b519 ‘The starting point of science is the formulation of statements about objectively observable phenomena. Common-sense knowledge also provides information about the material world.’ [[Ayala, ‘Autonomy of Biology as a Natural Science’, 1972|(Ayala 1972, 1)]] ‘The distinction between science and common-sense knowledge is based upon the joint presence in science of at least three distinctive characteristics. First, science seeks to organize knowledge in a systematic way \[…] \[Secondly, s]cience attempts to discover and formulate the conditions under which the observed facts and their mutual relationships exist. Thirdly, the explanatory hypotheses provided by science must be genuinely testable, and therefore subject to the possibility of rejection.’ [[Ayala, ‘Autonomy of Biology as a Natural Science’, 1972|(Ayala 1972, 1)]] ^30cb84 ‘\[…] science develops by discovering new relationships which show that observational statements and theories that had hitherto appeared as independent are in fact connected and can be integrated into a more comprehensive theory.’ [[Ayala, ‘Autonomy of Biology as a Natural Science’, 1972|(Ayala 1972, 2)]] ^c53813 ‘Reduction of one theory or branch of science to another has repeatedly occurred in the history of science. During the last hundred years several branches of Physics and Astronomy have been to a considerable extent unified by their reduction to a few theories of great generality like Quantum Mechanics and Relativity. A large sector of Chemistry has been reduced to Physics after it was discovered that the valence of an element bears a simple relation to the number of electrons in the outer orbit of the atom.’ [[Ayala, ‘Autonomy of Biology as a Natural Science’, 1972|(Ayala 1972, 2)]] ^05d029