The hot topic for discussion this weekend isn't the National Day Rally speech the Prime Minister is delivering this evening.

It is, instead, the coming general election. No one knows the date except the PM and his close confidants. But the entire nation has been in "election season" in the words of the People's Action Party organising secretary Ng Eng Hen, since the release of the Electoral Boundaries Review Committee report on July 24.

Nearly every day for the past week, the incumbent PAP and its challengers have been calling press conferences to introduce potential candidates. Everything is being seen through the lens of the coming GE. Even the Jubilee weekend celebrations around Aug 9 were tinged with election hues. Certainly the Rally this evening will be viewed through election lenses.

Apart from the question of When it will be held, there are questions of Who. Who's standing in which constituency? Who's stepping down? Who are the new candidates, from the PAP and the opposition?

But by far the most interesting question revolves around the What.

What is this election about? What is it going to be fought on? What matters to voters?

Every political party and candidate that wants your vote will promise to serve you, the voter. Every political party will have its own take on what this GE is about.

Gleaning from what has been said so far, the PAP will likely say this GE is about the future. The party needs the support of voters so it can bring in a team of people who can form the leadership of the future, to bring Singapore to greater heights.

The PAP has lined up a slate of candidates it hopes to see in Parliament who can augment the future leadership teams. But as Dr Ng underlined it, succession depends on voters' choice. If those intended future leaders don't get voters' support, the succession plan is thrown into disarray.

The Workers' Party will want to build on its First World Parliament appeal. The Singapore Democratic Party and Reform Party have been consistent in demanding more transparency and accountability from the PAP government. The Singapore Democratic Alliance and Singaporeans First look set to tap into a groundswell of anxiety about foreigners and campaign on platforms of putting citizens first.

It isn't clear what the Singapore People's Party, National Solidarity Party and Democratic People's Party, will stand for this election, given their leadership changes.

For the individual voter, the What question boils down to one simple thing: What is your vote going to depend on?

I started to think about this once election season kicked in. The campaign period will be full of sound and fury, and I wanted to reason things out first.

I am mindful that people base their vote on all manner of things. Kinship or communal ties matter: my late father once told me he voted for a candidate surnamed Chua!

People vote for candidates they like or who have done something for them. Or perhaps they support one candidate to spite his rival.

But when we try to be rational, I am sure Singaporeans will cast the vote according to what they think is best for the country.

In that context, there is only one question that matters for me this GE: Which is better for the future of Singapore - a stronger PAP or a stronger opposition?

Singaporeans know we are at an inflexion point in the nation's political development. The 2011 GE, which saw the opposition win six seats, backfooted the PAP.

Whatever PAP ministers may say, Singapore voters will remain convinced that the policy changes since 2011 - slowing down the influx of foreign talent; speeding up housing development and public transport infrastructure - are direct responses to the rise in support for the opposition. So, too, the move to introduce universal health insurance for life, and to expand early childhood subsidies beyond the low-income to the middle-income.

Having gotten a taste of blood, so to speak, some voters will press on to support the opposition, hoping to see more of such redistributive policies. Those who think a stronger opposition is good for Singapore will welcome this.

There is also the argument that a stronger opposition is good for Singapore's political development, not just as leverage against the PAP. Even some PAP ministers have said this.

According to this view, a strong opposition provides checks and balances on the ruling party. It sets Singapore further along the path towards a two-party system, the dream of political liberals who do not buy the PAP's argument that Singapore is so tiny and so exceptional, it can only be governed by the PAP's pre-selected A-team of political leaders, and that it lacks the talent base for other parties to build up a credible alternative. Each election that sees capable individuals joining the opposition dents that argument.

All that is needed next is for those capable individuals to coalesce around one or two serious political parties and their leaders, learn to compromise and work together, and win voters' support. Singapore can then become a "normal" country with a political system that remains stable even when parties alternate in power.

It may undergo a period of turbulence in the transition, but settle into a stable equilibrium. Then, the biggest risk for Singapore - of having a system untested by alternation of political power - will be neutralised.

Ergo, the patriotic voter who cares about the country's long-term future must support the opposition. Even if the opposition candidates are not as strong as the PAP ones, supporting the opposition is a principled stand to adopt, some will say.

But one can also make a convincing case for the opposite point of view: That a stronger PAP is more important for Singapore's future.

The first-order argument is simply that the PAP remains the best, and only, political party able to lead the country successfully.

Thus, it deserves voters' support, especially when it is trying so hard to get a new team elected who can join existing ministers to form the nexus of the future fourth-generation political leadership. No other party comes close to having a slate capable of governing the country.

The second-order argument is that the PAP is changing, and deserves support to nudge it along that trajectory of change: Of being more inclusive, and more empathetic of the struggles of the common man.

The third-order argument - commonly made by those who fear the PAP is becoming too populist - is that it is important to support the PAP in this GE, so they can reclaim lost moral and electoral ground.

Then they can have the political capital and confidence to govern, not just appease voters. Then they can make the policy trade-offs necessary for Singapore's future.

This is a variation of the fear among fiscal conservatives that a further slide in support for the PAP will see it lurch further left - towards fiscal profligacy, which would be disastrous for the country.

Those who think this way want to strengthen the PAP's political hand so it can afford to be less "populist".

Then there's the "last chance before the door slams shut" theory.

It goes like this: Support the PAP this GE2015 so it can put in place a team to lead Singapore into the future. The going will get tougher in future elections, as younger generations come of age - those who take Singapore's wealth for granted, who have never lived the miracle of going from Third World to First in their own lives, and who are restless for change.

Those who think like this will argue that it's important to support the PAP while your vote still makes a difference. Come GE2020 or 2025, it might too late, with too few drops of PAP votes in an ocean of opposition support.

The choices, to sum things up, are: Do you want to strengthen the PAP so it can consolidate and continue its 56-year record of successful governance (since self-government in 1959)? Or strengthen the opposition in the hope that a good alternative party will be built up, paving the way for a two-party system that could be more stable for Singapore?

Luckily for us all, there are a few more weeks to figure it out before Polling Day.