Philosophy of science
Philosophy of science is concerned with what makes hypotheses strong and how one can confirm theories; Should they be verified, confirmed, disconfirmed or falsified? Verification is rare in natural science since it requires a set of observations that logically lead to the hypothesis in question. Underdetermination will always interfere and make it possible that it’s a different hypothesis that explains the observations. Underdetermination is strongly linked to induction – it isn’t possible to know all the logical possible empirical observations. There is always room for unforeseen observations or explanations. A set of observations can almost always be explained by several different hypotheses. This is exemplified by the story of Horror Vacui. The observations are the same and can be explained both by nature having a fear of empty spaces and that the atmosphere creates a pressure. Therefore, we need more criteria for accepting a hypothesis other than that it explains the observations.
Underdetermination was one of Popper’s concerns with verification as the scientific method. He therefore believed the most secure and productive method was falsification. By falsification he meant constantly trying to prove a theory or hypothesis to be wrong. Every time a scientist doesn’t succeed in proving it wrong the hypothesis or theory has been confirmed. This doesn’t entail it being verified but only that it now is more likely to be true than before – Popper called this that the hypothesis or theory had been corroborated. But falsifying a hypothesis isn’t easy and it is important to remember that there is no form of ‘final’ falsification. It is always possible that our hypothesis is falsified by a mistake we made, and not because it is wrong. That is one of the reasons why it’s important to have an overview of the auxiliary hypothesis that are in use – sometimes they are the ones that need change or the ones being falsified VINCENZO, C. 2016. Confirmation. In: ZALTA, E. N. (ed.) Standford Encycplodia of Philosophy. Center for the Study of Language and Information (CSLI), Stanford University..
Science has philosophical prerequisites since scientist works on the foundation of an empirical and objective world searching for an objective truth. Philosophy of science is working with these assumptions arguing why they are necessary for science - and arguing why they are not sufficient. A scientist has to be a fallibilist, meaning that there shouldn’t be premises above criticism.
Testimony in science
In the scientific community there is collaboration in almost every aspect of science. Our amount of accepted knowledge is too vast and complex for one scientist to understand all of it. As a scientist one needs to be able to base one’s research on the testimony of other scientists. That is also why researchers refer to other articles which forms the basis of their knowledge, and quite possibly helps them think of new hypothesis to test.
Referring to other researcher’s articles helps to carry the burden of proof but it also works as an internal control of the different research areas.
There seems to be an incompatibility between what we normally think of science and the idea of testimony; The idea behind science is thinking by one self and being a fallibilist. But when it comes down to working as a scientist there are presumptions that we accept due to where it comes from. If my professor tells me that something is true, I tend to believe him. The problem occurs when choosing which expert is a true expert.
Confirmation in science
When confirming a hypothesis one needs relevant empirical consequences that are true or actually observed. This means that if one experimentally tests a hypothesis or theory and it then survives, then it seems intuitive to think that it might be a true hypothesis or theory. The confirmation is relative to a set of background beliefs that are necessary to limit the confirmation. The background beliefs also function as auxiliary hypotheses which describes the beliefs and assumptions that are constitutive for the hypothesis’ confirmation. For example: For every F, then G confirms Ga if Fa is present. The constraint forbids that the junction of Ga and Ha (something irrelevant) can’t confirm the hypothesis “for every F, then G”. Since the hypothesis is about F’s and G’s then the evidence should be too (Fa and Ga and not Ha) Put formally: Ga confirms relevantly (1): ∀x(Fx → Gx) given Fa. As constraint: Ga∨Ha doesn’t confirm (1) given Fa. Otherwise there is room for cheap confirmation, where the hypothesis is confirmed with non-relevant evidence SCHURZ, G. 2013. Philosophy of Science: A unified approach, Routledge..
The problem of induction as told by David Hume
David Hume stated that we can never know something with complete certainty. Our knowledge will always be based on a finite set of observations. Hume believed there to be only two types of statements in the world: Relations of Ideas and Matters of fact. Relations of ideas are before our experiences (a priori) as opposed to Matters of fact that are a posteriori (after experience). Since our experience is limited, matters of fact will never be certain – because it isn’t a priori. The problem of induction is that we try to generalize from matters of fact to relations of ideas: from uncertain and limited experience to certain a priori ideas.
Our habits make us draw causal inferences: when I have observed several times that when I drop a stone from midair it falls to the ground – then I start to expect it to happen again and again. I say that it must be so – I state something about the future based on my past, instead of basing it on a priori knowledge. But when shown in formal logic, it seems clear that it isn’t a valid judgement:
- All Fx observed have also been Gx
- a is a F
From (1) and (2) it doesn’t follow with certainty that a is a G. There is, for Hume to see, no way of knowing that it will always happen, since we cannot see the causal connection – we can only observe the constant conjunction of dropping the stone and its falling.
The problem of induction is then that science extrapolates a priori truths from limited observations. There is no clear and logical reason for this to be acceptable as a general law VICKERS, J. 2016. The Problem of Induction. In:ZALTA, E. N. (ed.). Standford Encycplodia of Philosophy: Center for the Study of Language and Information (CSLI), Standford University..
As conclusion we have a clear lack of absolute certainty in the natural sciences. Both because of the Humean problem of induction but mostly due to common errors and lack of understanding of the causal relations between objects. The lack of proof calls for more confirmation. In praxis this is partly solved by reproduction.
Scientific reproduction is a virtue of good science. For a theory to commit to it, it needs to be explained well enough so that another scientist can do the same experiments. The protocols need to be clear and all different results should be taken into consideration.
This is also relevant when discussing the Precautionary Principle. There we see the same problem - there doesn’t seem to be anything in natural science that can be known with absolute certainty and the consequences of a hypothesis can therefore never be fully anticipated. The decisions have to be made on an uncertain foundation, and which decision to take seems to come down to which experts one listens to. Therefore, testimonial evidence is an important part of the scientific community – the policymakers aren’t normally in the laboratory, finding their own results.