📖 Scientific principles and process

The method


Science provides models for harnessing knowledge in a relatively objective, material and quantified environment. It involves high levels of reproducibility and peer-to-peer confirmation of findings, and as such can produce very widely applicable and powerful knowledge. The downside to this is that due to its basis of formulating testable hypotheses, many types of knowledge remain outside of the working field of science.


Starting out with an idea based on previous knowledge or new observation, a testable hypothesis is established as the foundation for experimentation. Hypotheses are statements to be tested. For example, “cats don’t have a food preference” is a testable hypothesis for an animal shelter in the UK, but would not be a testable hypothesis somewhere where there are no cats. A hypothesis might not be testable due to abstract constraints e.g. “people are not happier on the Moon than on Earth”, or due to the limitations of human existence at a given time e.g. time, money, politics, priorities, taboos, etc.


The default hypothesis in any case is the null hypothesis that states no change will be observed. For example, “cats don’t have a food preference for wet or dry food” is the null hypothesis. “Cats prefer wet food to dry food” is its counterpart alternative hypothesis. A statistical test on data obtained from experiments might show that the null hypothesis is to be accepted or rejected.


Once within the space of a testable hypothesis, experimental design follows. This is a preparatory exercise ahead of experimentation that ensures the experiments and outcomes are what they need to be. Experiments must adhere to guidelines such as risk assessment, reproducibility and validity of results, time and cost effectiveness, etc. For example, in a clinical trial where clinicians administer drugs and placebos randomly to patients, a double-blind experimental design is required where neither the clinicians nor the patients are aware of …

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