English has become the universal language of science, after replacing German and Latin. Before the Second Wold War, scientists sometimes published in their local language, but chose Latin to reach an international audience. Since science is more global than ever, the need for a universal language remains; not only will the work you publish reach a larger audience, you're also able to access more information yourself. But, agreeing we need a universal language in science, is English the best option?
"It's unfair for non-native English speakers."
Native English speakers will have a certain advantage, as they don't require to learn a new language to engage in science.
"Editors focus more on a manuscript's English than on its scientific content."
This can happen, and editors should strive to judge the science, not strictly the language. This issue won't be excluded by using another language for science, though.
"Only using English in science may come with a bias, and lead to wrong conclusions."
Though this could be possible, research into this claim has not been able to confirm it. Moreover, other languages would have the same theoretical risk, and one might argue that people using English as a second language might have less of this problem, as non-native speakers use two sets of language skills to represent their findings, and so get sort of a second point of view.
"Old local knowledge will become inaccessible."
This objection tends to come up in this discussion, but I think it has less to do with English becoming the language of science, and more with the disappearance of old and rare languages overall. (The prime example for this argument comes from Australia, where English replaced Aboriginal languages. This doesn't involve a change in science language, but a change in language overall.)
"Having no native speakers in science would be worse."
Choosing Latin or another neutral language for science would only amplify the downsides. If the language is a hurdle for everyone, that will affect understanding among scientists (and the public).
The advantage that native English speakers have comes with the responsibility to help their non-native colleagues and be generous in their judgement of the English used by non-native speakers. (This is stated very well in this article.) Having some native speakers is better than none at all.
"A neutral language is inaccessible for the public."
Languages without native speakers, such as Latin, would exclude the public from science, while the opposite should be happening.
"English is among the most influential languages, so it fits the role."
Languages like Mandarin or Spanish are spoken by more people worldwide than English, but according to research done in 2014, these languages are not more influential. In this study, speakers need to be literate and online to increase their languages' influence. Dutch, for example, has a disproportionately high rating because the Dutch are "very multilingual and very online". English has become the language of science by filling in German's vacant position after World War II, German having been forbidden in the US, and Germany itself not producing science after the war. This is not to say English is therefore the best choice, but apparently it currently fits the needs of science.
I think it's crucial to note that English was not randomly picked, but rather filled the gap that German left as the top language in science. The increasing globalization then amplified its position, and therefore it isn't realistic to change that in the near future. It's important that those who are native English speakers are aware of their position, both as editors and as fellow scientists, and extend a hand to those who are not.