How much do we value our forests, and are they worth protecting?
"Not really, there is nothing to see in our forests... so I would say, build away," a banker friend told me. Another added that to get his nature fix, there are far better alternatives overseas.
These are typical answers I get when I ask laymen about the possibility of the Cross Island Line tunnelling under Singapore's largest nature reserve.
Yes, there has been strong debate over the issue. But it seems that the loudest voices belong to those involved in the green movement.
Chatting with friends and family, I found that many are indifferent to the Central Catchment Nature Reserve - home to at least 413 species of plants, 218 species of birds, 30 mammals and 24 freshwater fish species.
Perhaps it all boils down to a nature deficit in Singapore.
The term is used by experts to describe how people are increasingly alienated from their natural world, and lack the chance to experience nature.
National Institute of Education's Associate Professor Vilma Ann D'Rozario, who is studying the well-being benefits that children obtain from learning outside the classroom, especially in wild habitats, said that while she has seen a growing number of people enjoying Singapore's nature areas over the last decade or so, "most Singaporeans are little aware that we have nature and wild habitats at our doorstep".
Going by my news feed on social media sites, it seems that for many Singaporeans, the nature experience is limited to lounging by the sea in a deck chair, or having a picnic or barbecue at a local park.
For the more adventurous, they turn to Mount Rinjani in Lombok, Indonesia, or the Taman Negara National Park in Malaysia.
But many are unaware of the wilderness that can be found in urban Singapore, whether in our nature reserves or our marine park.
Said Prof D'Rozario, who volunteers extensively in environmental and wildlife conservation projects in Singapore: "Singapore has lovely green spaces, such as neighbourhood parks and gardens, which are enjoyed and used. But not as many Singaporeans visit our forest reserves.
"If more people visit our local forests, they would learn to understand forest systems better, appreciate our dependence on and interconnectedness with wildlife and wild habitats, and better develop a passion to protect and conserve our wild places, such as the Central Catchment Nature Reserve - our natural treasure."
Mr Eugene Tay, founder and director of environmental consultancy Green Future Solutions, also pointed out that this nature deficit could be shaped by Singapore's national narrative, which usually revolves around the Republic being a small country with no natural resources, a garden city with trees and parks that are manicured and recreational, and a pragmatic society driven by constant urban change.
He said: "This has shaped our mindsets such that some Singaporeans think that we do not have much biodiversity in our small country, and that our small hills and forests are less worthy compared to the majestic mountains and vast forests in other countries."
But, does size really matter?
Our nature reserves may be far removed from the likes of Yosemite or Yellowstone national parks in the United States. There are no waterfalls, meadows and vast wilderness teeming with large animals.
But our forests are teeming with life, even if it is not immediately obvious.
As Professor Peter Ng, head of the Lee Kong Chian Natural History Museum, puts it, "not seeing is not the same as not there".
"The area is rich… not world-beating rich, but Singapore rich. It is not about how much, but what is ours 100 per cent," added Prof Ng, who in 1986 discovered the Johnson's freshwater crab, a species that can be found only in Singapore's Bukit Timah and Central Catchment Nature Reserves and nowhere else in the world.
Mr Sankar Ananthanarayanan co-founded nature group Herpetological Society of Singapore to raise awareness about reptiles and amphibians.
Not only are they often perceived of as being dangerous, herps (reptiles and amphibians) are also smaller, harder to spot, and less "cute" than charismatic tigers and elephants.
"People may not see them, even though they're right in front of them," said Mr Sankar.
In the MacRitchie area of the Central Catchment Nature Reserve alone, some 56 reptiles and 17 species of amphibians have been recorded.
National University of Singapore biologist David Tan, who volunteers with the Love Our MacRitchie Forest group, said it may be more difficult to spot organisms in a tropical rainforest than in a temperate forest, as the former has a greater variety of plant and animal species.
This makes wildlife much more difficult to find because there are more places for it to hide and more predators driving it to stay out of sight.
But out of sight should not be out of mind. The biodiversity is there, it is just that spotting them requires some scientific knowledge - or lots of patience and luck.
When I visited the reserve last Friday, for instance, I saw a chestnut-bellied malkoha in flight, its iridescent feathers spread out as it swooped from tree to tree.
It is a rare sighting - the last remaining malkoha species out of three that can still be found in Singapore - and one that happened entirely by chance.
Even then, there is so much else to see.
Advised Mr Tan: "Go on a hike and climb to the top of the Jelutong Tower for a bird's eye view of the Central Catchment Nature Reserve... you cannot seriously say that it can't compare to any other national monument - the tropical forest is a spectacle to behold.
"And a tropical forest within an urban metropolis? Even more so."
Our nature areas may not be large, but as Prof Ng pointed out, they are ours, they are uniquely Singapore, and they should be protected and restored for our future generations.
The Central Catchment Nature Reserve is the Republic's largest nature reserve at 2,000ha - the size of almost 2,500 football fields.
It is also where Singapore's largest primary lowland rainforest patch can be found. Once abundant in Singapore, the trees were felled to make way for human settlements and less than 0.5 per cent of our original primary forest cover now remains.
Within the reserve is an even rarer forest type - the 750ha Nee Soon Swamp Forest, Singapore's last remaining primary freshwater swamp forest.
Before the early 1930s, such habitats could also be found in Upper and Lower Seletar and Jurong. These areas have been converted for other land uses.
Said Prof Ng: "At the end of the day - what is nostalgia and heritage worth? Nothing really. In dollars and cents at least. But that same sense and feel of nostalgia, memories and remembering makes us human - makes us sentient. It connects us to the land and the community. Shared memories - good and bad.
"Can it be measured in dollars and cents? No. Is it therefore a waste of effort and time? No."
Nature groups are uniting under one banner, the March for MacRitchie movement, to call for an alternative route to save the forests.
Volunteers are giving their time to conduct free walks through the reserve, to help people realise the nature in our own backyard and share its beauty.
Mr Tan said: "Just take two hours of your time, visit the forest, and come see what lives in there.
"You'll see that there's plenty worth protecting, and best of all, it's free."