Gregory's ServerAll or any of them. I'm English but live in France, so it's clear to me that the French 'centre' is well to the left of the English (as, incidentally, is the Scottish). In Saudi Arabia a centrist policy on, say, gender equality, or gay marriage, is going to be very different from a European centrist view.
Centrism is the ideology of the status quo, whatever that might be. It's for people that have been socialised in a particular world-view and lifestyle and don't really question it, or think about it much at all; its political theory is: 'Things are not too bad, I'm pretty comfortable with the way we're living, change is risky, best not to do too much'.
And this is one reason why, I think, it's so hard to get to necessary action on climate-ecological breakdown: the political centre accepts the science - respecting science and scientists has been very much part of their socialisation - yet still resists adequate action to avert catastrophe.
The left, on the other hand, grounded in fighting for those oppressed and exploited in the status quo, has always embraced the view that humanity is capable of organising itself on the basis of evidence and reason, for the benefit of all - so it easily now embraces the rational choice of radical action on climate-ecological breakdown. (While the right naturally embraces irrationality, superstition, and retires into conspiracy theories and 'culture wars'.)
@GeofCox @GryphonSK Conservatism is the ideology of the status quo. It's in the name.