They are not, as the public seems to assume, self-obsessed, but care enough about others to lift their eyes so as to take a wider view.
What usually distinguishes them from other people is that they almost always have well-defined views about how they could make life better for our fellow-citizens.
We might conclude, having seen them in action, that they delude themselves in thinking that they (or their views) can make a difference for the better, but I have no doubt that their intentions and motives, in most cases, are genuine.
I know from my experience of the notoriously rowdy and at times badly behaved British Parliament, that the public are likely to conclude that politicians are, by definition, uniquely prone to such bad behaviour.
But, I would tell the critics, such behaviour is a function of the situation they find themselves in. Most members of the public would react in a similar way if they were compelled to sit and listen to people just a few feet away, uttering - as they saw it - offensive nonsense.
Setting all that aside, parliament is made up of a range of different types of people - just as you would find in any random selection of the public, such as you might find at a rugby match or a pop concert.
You will find in parliament all the expected stereotypes. There are those who are full of themselves and whose ambitions exceed their abilities.
There are those who are "warriors", whose main buzz is gained from identifying and castigating those whom they regard as enemies.
There are those who have little to commend them, in the sense that they are content to toe the party line and to let others do their thinking for them.
But there are many who are dedicated to serving, as they see it, their constituents and who genuinely believe they have a clearer idea of what is needed to create a good society - and who are ready to take "the slings and arrows of outrageous fortune" in order to work for that goal.
One other cautionary word. There is a view in some quarters that "all is fair in love and war - and politics" - in other words, politicians should be excused for behaving badly, because the political battle requires and allows them to be dishonest and mean-minded.
I reject that view. Politicians should behave in their political lives as well as they would be expected to in their personal affairs.
The voters are entitled to judge them as people and to mark them down if either their political or personal behaviour falls short of what we would normally expect from someone of high personal standards.
Our most successful politicians understand that, and are able to demonstrate they are "nice people" in the widest sense.
John Key, for example, won elections because most people recognised his affability and charm (even if those qualities masked a ruthless political awareness and sometimes a willingness to dissemble).
And what a pleasure to discover that Jacinda Ardern, whose compassion, care and empathy have made such an impression worldwide in her role as Prime Minister, demonstrates similar qualities as an ordinary citizen in her day-to-day interactions with members of the general public.
Bryan Gould is an ex-British MP and Waikato University vice-chancellor.