Almost every time there's a debate about getting rid of the monarchy, people will say: "but who would be president?"

It's a strange question. The answer is obvious: "who we choose".

We can't possibly give names, because we don't know who will be potential candidates at the time, and the best we could do is guess at possible first presidents. After that no-one has any idea who our presidents will be.

But that's ok. Because we do know it'll be who the country votes for.

President Johnson or Blair?

• Are the royals the best on offer as a future head of state?

Then people complain that it will be a former prime minister. It used to be "President Thatcher?" The names change but the point stays the same: the voters can't be trusted to make a sensible choice.

What people seem to be telling us is that they don't trust the voters. But they are also suggesting that Charles, William and George are the best the country can hope for when it comes to a head of state. The people couldn't possibly make a better choice.

Some even argue that voters are so juvenile and silly that we'll vote for which ever celebrity is flavour of the month. David Beckham and Joanna Lumley have often (and unfairly) been touted as arguments against letting the voters choose.

The reality is that in a country the size of the UK, a country awash with talent and amazing people, we will be spoilt for choice. Ireland manages to choose excellent heads of state for the same reason we can too. They take the position seriously and there are plenty of good candidates to choose from.

As for Blair or Johnson. We rarely meet anyone who wants either of them as president, so what are the chances they'll be elected? Prime ministers become former prime ministers for a reason, they lose popular support. But if they are elected then that's the choice of the voters, and it's the voters' right to choose who they think is the best candidate on offer.

• Irish president Michael D Higgins with former presidents Mary McAleese (r) and Mary Robinson (l) standing behind him.

How it works in other countries

Republic proposes a directly elected head of state, similar to the system in Ireland. In Germany the president is elected by a special convention made up of the federal parliament and representatives of the states (Lander). In other countries it's the parliament who appoints the president. All these options are legitimate and democratic, but we believe direct election is the best, most democratic and fairest way to choose a head of state.

As in Germany, Ireland, Italy, Greece and elsewhere, the head of state wouldn't have political power, but a limited constitutional and ceremonial role. They are often limited to two terms in office and are required to remain non-partisan once elected.

• German president Frank-Walter Steinmeier (l) speaking with former president Joachim Gauck (r). Gauck was previously a civil rights activist in East Germany.