Science, as the most formal and elaborate development of objectivity, is the most focused expression of the realist faith. To play her role as observer, the scientist must assume that the observed domain is a single world ruled by universal ‘laws’ operating independently of all observers. In order to contribute to the consensus on what those ‘laws’ really are, then, she must do what she can to eliminate idiosyncrasies from her own observations.
The striving for objectivity is thus understood, phenomenologically, as a striving to achieve greater consensus, greater agreement or consonance among a plurality of subjects, rather than as an attempt to avoid subjectivity altogether.
— David Abram (1996, 38)
Scientific inquiry aims at a consensus constrained by experiment: we test a hypothesis by drawing predictions from it, i.e. deducing what would happen in a specified situation if it were true, then observing what actually happens in that situation. If the experiment is well designed and produces an observation contrary to the prediction, the hypothesis is refuted or ‘falsified’; a positive result, though not conclusive, tends to confirm the hypothesis.
The failures as well as the successes of the predictions must be honestly noted. The whole proceeding must be fair and unbiased.
Some persons fancy that bias and counter-bias are favorable to the extraction of truth—that hot and partisan debate is the way to investigate. This is the theory of our atrocious legal procedure. But Logic puts its heel upon this suggestion. It irrefragably demonstrates that knowledge can only be furthered by the real desire for it, and that the methods of obstinacy, of authority, and every mode of trying to reach a foregone conclusion, are absolutely of no value.Peirce, W3:331 (1878)
This in a nutshell is the objectivity proper to science – that is, to all honest argument. It amounts to respecting the reality of the object observed rather than clinging to the observer’s or experimenter’s bias. In other words, it relies crucially on inductive logic.
It is of the essence of induction that the consequence of the theory should be drawn first in regard to the unknown, or virtually unknown, result of experiment; and that this should virtually be only ascertained afterward. For if we look over the phenomena to find agreements with the theory, it is a mere question of ingenuity and industry how many we shall find.
Peirce, BD ‘Reasoning’